Mycobacterium avium paratuberculosis Infection Suppresses Vitamin D Activation and Cathelicidin Production in Macrophages through Modulation of the TLR2-Dependent p38/MAPK-CYP27B1-VDR-CAMP Axis.

This study characterized the primary mechanism by which MAP infection leads to diminished levels of active vitamin D and cathelicidin in CD patients, which may explain the exacerbated vitamin D deficiency state in these cases.